Brian is a professor in geological sciences at the University of Colorado, Boulder, where he studies Mars with a focus on understanding how and when Mars could have been habitable by life as we know it. This research program includes studying craters (me!), valley networks, other evidence for water, and traipsing around Earth for analogues for Mars, including studying extremophiles on active volcanoes.

The interview is mostly main-stream, covering a lot of the basics, but we get into some of the “PR Fails” of NASA, including the GFAJ-1 “arsenic” bacteria from two years ago and the ALH84001 Martian meteorite “nano-bacteria.” And, no discussion about Mars would be complete without a Hoagland name-drop once or twice.

Since this is an interview episode, and since it’s an hour long, only the Puzzler segment is present in addition to the main interview.